The effects of resistive loads applied at the mouth were compared to the effects of bronchospasm on ventilation, respiratory muscle force (occlusion pressure), and respiratory sensations in 6 normal and 11 asthmatic subjects breathing 100% O2. External resistive loads ranging from 0.65 to 13.33 cm H2O/liter per s were applied during both inspiration and expiration. Bronchospasm was induced by i...

Knowledge of the airflow distribution inside a Tunnel Boring Machine (TBM) can create a safe working environment for workers and machinery. The airflow quality and the related mass flow rate in the ventilation system should be sufficient to dilute gases and remove dust inside the tunnel. In this work, airflow distribution in the single shield TBM tunnel was studied using computational fluid dyn...

OBJECTIVES The purpose of this study was to determine the aerodynamic and acoustic features of speech produced at comfortable, maximal and minimal levels of vocal effort. STUDY DESIGN Prospective, quasi-experimental research design. METHOD Eighteen healthy participants with normal voice were included in this study. After task training, participants produced repeated syllable combinations at...

BACKGROUND Whether respiratory muscle training is of benefit to patients with chronic airflow limitation is controversial. The objective of the study was to determine the effect of resistance breathing training on physiological and functional measures in patients with chronic airflow obstruction. METHODS The design was a randomised, double blind, controlled trial with a six month follow up. E...

The adhesive external nasal dilator strip (ENDS) is widely advocated for prevention of snoring and promotion of nasal breathing during exercise. In the present study, the effects of the ENDS on nasal airflow resistance (Rn) in normal subjects were examined and factors determining individual responses to the ENDS explored. Using posterior rhinomanometry, 20 healthy Caucasian adults (10 males, 10...

The resistance of solid-separated solid wastes (SSDWs) to moderate airflow ranging from 0.05 0.30 m3/s-m2 was measured at various bed depths and moisture levels. pressure drop across a loose-fill fixed column observed increase more rapidly with increasing rates than depths. An in the content (10 percentage points) caused decrease by an average 13.2–17.0%, evaluated within 10–40% (MC) range. A f...

OBJECTIVES This study sought to better define the clinical characteristics of severe asthma in both children and adults, and to evaluate the effect of asthma duration on multiple parameters of disease severity. DESIGN Retrospective analysis of prospectively collected data on 275 patients (125 children) with severe asthma who were admitted to a tertiary asthma referral center. METHODS Demogr...

The cervical sympathetic trunks innervate the carotid bodies, carotid baroreceptors, thyroid gland and the upper airway mucosa, structures which can influence breathing and upper airway resistance. However, their role in the control of ventilation and upper airway patency is poorly understood. A constant airflow was applied to the upper airway through a high-cervical tracheostomy in anaesthetiz...